1. Field of the Invention
This invention relates generally to exercise and back therapy apparatus, and more particularly to a back therapy and exercise station on which performance of various therapeutic, stretching, bending, twisting and inversion exercises may be carried out utilizing the user's weight for fully flexing and decompressing the spine and strengthening the trunk and back muscles of the user.
2. Background Art
The human spine or vertebral column is a complex structure which is designed to support loads, protect the spinal cord, and attenuate the forces that are commonly transferred to and from the trunk and arms to the lower extremities. The vertebral column is made up of 24 true vertebrae, seven cervical, twelve thoracic, and five lumbar. There are five sacral vertebrae, which in the adult are fused together, thereby not representing true vertebrae. There are three major curves associated with the vertebral column that are functional in the support of the body. The lumbar and cervical curves are convex anteriorly, whereas the thoracic curve is convex posteriorly. There are normal deviations from vertical in the coronal plane as well.
Each vertebra is separated from adjacent vertebrae by intervertebral discs, which function as shock absorbers between the vertebral bodies and maintain the space between the vertebrae open sufficient to insure that the nerves and the blood vessels can pass between them without injury. There are two major components of discs, a viscous inner portion called the nucleus pulposis and a tough fibrous tissue surrounding the nucleus called the annulus fibrosis. Due to the forces that the vertebral column commonly experiences, the annulus will sometimes become herniated allowing the nucleus to seep out of confinement. The flow of the nucleus out of the annulus will often impinge upon spinal nerves causing clinical problems ranging from pain to quasiparalysis. This is commonly referred to as a “slipped disc.”
The individual vertebrae and intervertebral discs are stabilized by vertebral ligaments. The posterior ligaments are those which tend to resist the vertebral column's tendency to flex, and the anterior ligaments are those which help prevent extension. The ligaments are strong and somewhat inelastic.
The musculature of the vertebral column is also extensive and complex. The anterior vertebral muscles are those which tend to cause vertebral flexion and include the abdominal muscles (rectus abdominus, the external obliques, and the internal obliques). The psoas major and minor muscles have attachments to the anterior aspect of the vertebral column in the lumbar region, and have a tendency to cause extension of the lumbar vertebrae. The primary extensors are those muscles which are classified as posterior vertebral muscles. A simplification of the muscles places them in a single group of muscles called the erector spinae.
The loads on the vertebral column come from three sources: body weight, external forces, and internal forces. Any particular vertebrae will be affected by the weight of any body mass that is superior to its location. External forces comprise any force, or weight, that is added to the vertebral column. Internal forces represent forces that are created by muscles and ligaments. The erector spinae, for example, which are found bilaterally just lateral to the vertebral column, cause the vertebral column to undergo compressive forces when they contract.
There are three basic types of forces that affect the vertebral column. In general, these are compression, shear, and torsion forces. Compression forces act predominately upon the intervertebral discs. Shear forces, however, have their predominant effect at the intervertebral foramen, the site at which spinal nerves exit from the vertebral column. Torsion forces are twisting forces and may affect both of these structures.
Tension is a force quite common in the vertebral column. During flexion of the trunk, for example, the anterior aspect of the intervertebral body undergoes compression as a result of the adjacent vertebral bodies moving closer to one another. The posterior aspect of the intervertebral disc, however, undergoes tension, as do the posterior vertebral ligaments which serve to restrict the degree of flexion which may occur.
Without proper muscular support the vertebrae become unstable, and if the discs flatten out or become damaged, decreased circulation an/or nerve function can result. The discs also flatten over a period of time as one ages principally due to the weight of the head, neck and shoulders, and gravitational stress constantly compressing the spine. Weak abdominal muscles, poor posture and lack of exercise all contribute to further weaken the muscular support for the vertebrae and can make a person more susceptible to back sprains or more serious injury. Painful and disabling low back disorders are caused by disc herniations (subligamentous and extruded), degenerative disc disease, sciatica and posterior facet arthrosis.
Freestanding exercise machines known as “Vertical Knee Raise” (VKR) stations are known in the art which utilize the weight of the user's body, without stressing the back, in performing various exercises such as knee raises, leg raises and oblique twists and bends, which, tighten the user's midsection and provide stretching and contraction of the back muscles to some extent. These types of freestanding stations also allow the user to perform chinning and pull-up exercises, which strengthen the muscles of the arms and upper torso.
Freestanding exercise machines known as “imversion machines” are known in the art, which utilize the weight of the user's body to decompress the spine via controlled traction in the cervical and/or lumbar spine areas. These types of devices effect decompression by suspending the body from the heels in an up-side-down manner, or suspend the body above a support surface by the thighs, pelvis or abdomen. Although some limited amount of exercise may be performed in an inverted position, most of these types of devices are designed primarily for spinal decompression and are not entirely satisfactory for fully flexing the spine and strengthening the back extensor muscles and toning the abdominal muscles, and the exercises performable on such devices are merely an incident of the inverted supported position.
Tension machines are also known in that art for the treatment of painful and disabling low back disorders caused by disc herniations (subligamentous and extruded), degenerative disc disease, sciatica and posterior facet arthrosis. These types of machines apply controlled tension along the axis of the spinal column to distract the vertebral segments and posterior facets of the lumbar spine and decompress the intervertebral discs. Some of these machines create a vacuum effect within the disc drawing the herniation back into place and drawing fluids back into the disc so they can heal. Although such treatment effectively reduces pain and improves the mobility of the back in a significant number of patients, these types of tensioning machines are designed specifically for spinal decompression and do not provide means for exercising and strengthening the back extensor muscles and toning the abdominal muscles.
The present invention is distinguished over the prior art in general by a freestanding back therapy and multiple exercise station on which on performance of various therapeutic, stretching, bending, twisting, extension and inversion exercises may be carried out utilizing the user's weight for fully flexing and decompressing the spine and strengthening the trunk and back muscles of the user. The station has a frame of tubular construction with a floor engaging base, front and rear vertical upright members, a horizontal top member extending between upper ends thereof, and a cushioned forearm pad on each said horizontal member with handgrips at outer of the horizontal top members. A lower pair of vertically spaced padded cross members extend transversely between the rear vertical upright members to serve as foot supports. A central upright member is connected at a lower end with at least one padded cross member and has a forward and angularly upward extending upper portion. A backrest pad is mounted the central upright member. An upper pair of parallel vertically spaced padded tubular members extend laterally outward from each side of the central upright member near its upper portion to selectively serve either as handgrips or as elevated or leg or foot supports when performing exercises. A removable rotatable cylindrical cushioned roller is may be mounted transversely between the horizontal top members to serve as a back engaging roller or a seating surface when performing exercises. Various auxiliary exercise apparatus may be removably connected with the station for performing a variety of exercises.